Toilet tank



FIG. 1 is a top, front, left perspective view of an embodiment of the claimed design;

FIG. 2 is a right side elevation view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a front elevation view thereof;

FIG. 5 is a rear elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The ornamental design which is claimed is shown in solid lines in the drawings. The broken lines in the drawings are for illustrative purposes only and form no part of the claimed design. Broken lines formed by equal length dashes in the drawings illustrate unclaimed portions of the design. Broken lines formed of unequal length dashes (i.e., dash-dot) show boundaries between claimed and unclaimed portions of the design. 

CLAIM The ornamental design for a toilet tank, as shown and described. 